Accessory Dwelling Units
Frequently Asked Questions

What are they?
Accessory Dwelling Units (ADUs), also known as "granny-flats", are additional living units that homeowners build on their property, often above a garage. In the 1940s and 1950s, many families would rent out these units as a form of supplemental income. However, since then, many communities have restricted zoning regulations, so these structures are no longer legal. Currently in Ann Arbor, these units can be constructed, but rent cannot be charged1. With a major affordable housing shortage facing the city, and urban sprawl causing negative environmental consequences, amending these ordinances to allow homeowners to charge rent could make modest positive steps towards ameliorating these problems.

Affordable Housing in Ann Arbor
Affordable housing is defined as "housing which costs the resident 30% or less of their gross income, regardless of income level". Ann Arbor ranks 140 out of 187 for affordability. Average monthly rental costs for Ann Arbor are $959, requiring an annual of income of $38,360 to be considered affordable. One person, working full-time at a living wage of $10.20/hour will only make about $21,2162.

Why is there a shortage of Affordable Housing?

  • Student demand for centrally located housing contributes to the high cost of rental property
  • There is a demand for high priced homes, which are more profitable for developers to make than affordable housing units are
  • NIMBYism (Not-in-my-backyard) attitudes among community members are further obstacles when affordable developments are proposed3

Urban Sprawl
Due to the high cost of living within the city, 75,000 to 85,000 people live outside Ann Arbor and commute to work in the city every day, many cars with single passengers. This influx of commuters causes increased emissions, air and water pollution, traffic congestion, and infrastructure costs. Furthermore, this sprawl contributes to the destruction of open spaces, farmlands, and wetlands4.

Ann Arbor's History with ADUs
In 2002, a proposal to change Ann Arbor's zoning ordinances to allow residents to construct ADUs and charge rent turned into a very contentious issue. Due to the amount of concern voiced by various neighborhood associations, City Council decided to table permanently the proposal5.

What obstacles prevented ADUs from being passed?

  • The public was not informed about and included in the decision-process from the start, so some of their concerns were misguided: Residents were concerned that bringing students into their neighborhoods would bring down the quality of the neighborhood. Noting the condition of neighborhoods composed of mostly students, residents feared their own neighborhoods would be transformed into these "student ghetto" areas with trash in the yards and noisy parties late at night6.
  • Because only two people would be allowed to live in the ADU, the main beneficiaries of the proposal would be students. Ann Arbor residents thought the U of M was irresponsible about providing adequate housing to students, and passing ADUs would reward that irresponsibility7.
  • Residents were concerned that the city would not devote energy to enforcement. While the proposed change required that the homeowner continue to live in the house, it would be difficult to make sure this rule was followed8
  • Increasing the number of people living in a neighborhood would further stress the already tight parking situation in the city9.

How can we overcome these obstacles to get ADUs passed?

  • By including the public/neighborhood associations in the decision-making process from the start, the proposal can be debated more fairly, and all parties can be informed about the effects ADUs will and won't have
  • While it is unfortunate that the U of M does not provide adequate housing for its students, the problems associated with urban sprawl and inadequate affordable housing, will not go away without taking steps to increase density within the city. If the city, the university, and Ann Arbor residents work together on this issue, steps can be made that improve the quality of our community for everyone.

1 Gantert, Tom. "Town-gown relationship, affordable housing are pro, con debate." The Ann Arbor News. 5 February 2002.
2 "Report on Affordable Housing in the Ann Arbor Area." Ann Arbor Area Chamber of Commerce. Housing Innovation Program. 2002.
3 ibid.
4 ibid.
5 Gantert, Tom. "City rejects accessory apartments." The Ann Arbor News. 5 February 2002.
6 Gantert, Tom. "Residents fear invasion of students." The Ann Arbor News. 3 February 2002.
7 "Good Move: Council preserves neighborhoods with vote against accessory units." Editorial. The Ann Arbor News. 5 February 2002.
8 Public Hearing and Action on Amendments co Chapter 55 regarding Accessory Dwelling Units. Ann Arbor City Planning Commission Minutes. 5 February 2002.
9 ibid.